Double lever tool for cutting open containers of sheet metal or plastic materials



June 2, 1970 K. KAPPLER 3,514,353

\ DOUBLE LEVER TOOL FOR CUTTING OPEN CONTAINERS OF SHEET METAL 0RPLASTIC MATERIALS Filed Aug. 16, 1967 I7 I I I Fig.3

IN! EN r 0R Karl Kapp/er ATTORNEYS United States Patent US. Cl. 30-14 3Claims ABSTRACT OF THE DISCLOSURE A double-lever tool for cutting opencontainers of sheet metal or plastic sheet material having a pair oflevers pivotally connected at one end, the levers at said one end formedwith a pair of projecting tongues. A spring at the one end of the leversholds the other ends of the levers apart. A knife blade is carried on afirst one of the levers. A fixed jaw and spring biased movable jaw iscarried on the other lever. The jaws engage a bead at the top of acontainer while the knife cuts open the top of the container at thebead. The knife blade is mounted in the plane of the first lever orperpendicular to the first lever to cut the side wall or top wallrespectively of the container.

The present invention relates to a double-lever tool for cutting opencontainers of sheet metal or plastic material with a bead projectingnear the rims of the opening to be made.

By the word containers all types of containers are meant having mutuallyperpendicular top and side walls joined together with a peripheral beadextending around the joint between the walls.

For opening such containers, bell-crank tools are known (German patentspecification 1,098,388). They have the disadvantage that they must beengaged several times (at least 5 times) and taken ofi again for cuttingoff a lid. As compared with this, the double-lever tool according to theinvention runs automatically along the rim of the container whenoperated after one single engagement until the container is cut open by360.

This advantage is obtained with the double-lever tool according to theinvention. The levers are spread by spring load and are manually pressedtogether for cutting. A knife blade is fastened on one lever of the toolwhile the other lever has clamping jaws engaging opposite sides of thehead during the cutting operation.

When the tool is mounted in a plane parallel to the container lid andthe lever are pressed together, the clamping jaws close and grip thehead. A part of the lid is thereby cut from the container. Then clampingjaws open and the lever carrying them is guided along the head into anew clamping position by the spreading spring.

When the levers are pressed together again, the clamp ing jaws firstengage the bead, and then the knife blade is pulled toward the jaws. Theknife blade may be fixed on the one lever parallel to the axis of theone lever. In this case the knife blade engages the side wall of thecontainer and cuts the lid with the bead. The knife may instead beperpendicular to the axis of the lever carrying the knife blade, and inthis case it cuts out the lid from the bead.

The clamping include a pin fixed on the second lever and a third leverpivotable on the second lever. The third lever has a jaw at one endformed with a pointed part and with an L-shaped part. The pointed partis urged toward the pin by a coil spring engaged on the pivot of thirdlever and having opposite ends engaged on the sec- 3,514,853 PatentedJune 2 1970 0nd and third levers. The third lever is manually turnedagainst spring bias to separate the pointed part of the movable jaw andthe fixed jaw or pin so that the bead of the container can enter betweenthem. When the third lever is released, the pointed part engages theouter side of the bead .while the fixed jaw engages the inner side ofthe bead. Then the first and second levers can be pressed together whilethe jaws remain in place and the knife blade is drawn toward the jaws.When the first and second levers are released, these levers separateunder spring bias while the knife blade remains in place and the thirdlever is automatically turned so that the shaped part of the movable jawslide along the bead along with the fixed jaw. At the end of travel ofthe movable jaw, spring bias on the third lever turns this lever so thatthe pointed part of the movable jaw again engages the bead.

The drawing shows diagrammatically and partially in section twopreferred embodiments of the invention.

FIG. 1 is a bottom plan view of the double-lever tool of the invention.

FIG. 2 is a top plan view on the tool according to the invention shownopening an oval can.

FIG. 3 is a longitudinal section through the knife leg of anotherembodiment of the double-lever tool of the invention.

The two levers 2 and 4 of the double-lever tool are spread according tothis drawing by a volute spring 13 surrounding the pivot 15. In theshown embodiment, the levers carry jaws 16 and 17 so that the tool canalso be used as a pair of tongs. On the lever 4, the knife blade 3 or 3'is fastened. It lies either parallel to the leg 4 or normal to it. Afixed clamping jaw is represented in the drawing by the pin 5 on lever2. A pivotable jaw which coacts with pin 5 includes a double-armed lever6 on bolt 12 which is fastened on the other lever 2. The lever 6 ispressed against the stop 19 by a volute spring 14 arranged around thebolt 12. The clamping jaws 5, 6, only open, if there is a force actingin the direction of the arrow 20. The head 10 of the container 7, 8 isinserted into the tool as shown in FIG. 3. The knife 3' cuts open theside wall of the container underneath the head 10.

In the embodiment according to FIG. 1 the knife 3 cuts open thecontainer lid 8 within the bead 10. In both cases (FIG. 1 and FIG. 3)the tool is held in a position overlaying the top wall 8 of thecontainer 7, 8 as shown in FIG. 2.

Initially bead 10 is inserted between jaws 5 and 6. When the levers 2and 4 of the tool are pressed together in the direction of the arrow 21against the effect of the spring 13, the pointed part of jaw 6frictionally engages bead 10 which is then clamped between this pointedpart and the clamping jaw or pin 5, while the knife blade 3 or 3respectively i forced into the container and cuts open the side wall ofcontainer 7 or the lid 8 respectively over the full length of thespreading angle of the levers 2, 4 of the tool. If now the compressedlevers are released they can spread open again under the effect of thespring 13. Lever 4 stops while the lever 2 runs downward on the bead 10(FIG. 2 of the drawing). The clamping jaws 5 and 6 release the bead 10for this purpose as the force acting in the direction of the arrow 20opens the clamping jaws 5, 6 against the effect of the spring 14. Thetool thus travels along the full rim of the container through 360 andopens the container by mere continuous pressing together and letting itspread again.

What is claimed is:

1. A tool for cutting open a container made of sheet material, saidcontainer having mutually perpendicular top and side walls joinedtogether, and a peripheral bead extending around the joint between thetop and side walls,

said tool comprising in combination: first and second levers; a firstpivot pivotally joining the levers together at one end thereof; a firstcoiled spring engaged on said pivot with opposite ends of said springengaging the levers at said one end thereof and urging the levers apartto define a V-shaped configuration; a cutting blade on the first leverfor cutting one of said walls adjacent to the bead; a pin defining afirst fixed jaw on the second lever for engaging inside said bead abovesaid top wall; a third lever; a second pivot pivotally securing thethird lever to the second lever with one end of the third lever disposednear said first jaw; said one end of the third lever being formed withan L-shaped part and a pointed part spaced slightly apart and defining asecond jaw; and a second coiled spring engaged on the second pivot andtending to urge said pointed part toward said first jaw, whereby thethird lever can be turned manually against bias in said second spring tomove the pointed part away from said first jaw to define a space intowhich the bead can enter when said one end of the first and second leveroverlays the top of the container, whereby the bead will be grippedbetween the first jaw and said pointed part of the second jaw underspring bias when the third lever is released, and whereby the blade willcut one wall of the container when the other end of the first lever ispressed toward the other end of the second lever, and whereby the thirdlever will pivot against bias in the second spring so that the L-shapedpart of the second jaw contacts the bead and slides along the bead withthe first jaw while the other end of the second lever moves away fromthe other end of the first lever. and while the blade remains engaged insaid one wall when pressure on the first lever is released, whereuponthe bead will again be engaged between the first jaw and pointed part ofthe second ja'w at the end of movement of the other end of the secondlever.

2. A tool as defined in claim 1, wherein said blade is disposed in aplane parallel to the first lever to cut the side wall of the'container.

3. A tool as defined in claim 1, wherein the blade is 4 disposed in aplane perpendicular to the first lever to cut the top wall ofthe'container.

References Cited UNITED STATES PATENTS GIL WEIDENFELD, Primary ExaminerUS. Cl. X.R. 714.2

